


UnderMortality (An Undertale AU)

by Cotton147



Category: Undertale (Video Game)
Genre: Angst, Fluff, Multi, POV First Person, Undertale AU, Undertale Spoilers
Language: English
Status: In-Progress
Published: 2020-09-26
Updated: 2020-11-12
Packaged: 2021-03-08 02:29:11
Rating: Not Rated
Warnings: Major Character Death, No Archive Warnings Apply
Chapters: 3
Words: 1,077
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26668243
Author URL: https://archiveofourown.org/users/Cotton147/pseuds/Cotton147
Summary: Frisk never knew what would happen if they never listened. Obviously something would happen, right?  But when an outside force pulls them towards the giant hole in Mt. Ebott, they find out that there is more to the world than they thought. Occupied with their new ghost friend, will Frisk free the monsters from the Underground? Or will they succumb to the outside forces threatening to use their body to crumble everything they know?
Kudos: 1





	1. Intro

**Author's Note:**

> This is my first Fanfic, So please excuse me if the spelling sucks or if there is not enough juice.

_Long ago, two races ruled over Earth: HUMANS and MONSTERS._

_One day, war broke out between the two races._

_After a long battle, the humans were victorious._

_They sealed the monsters underground with a magic spell._

_Hundreds of years later, the monsters were still trapped._

_Until one escaped._

_The pitter-patter of feet slowed at the entrance to the ruins. The place where all humans fell._

_The figure gently laid the body of a young girl onto the flowers._

_“Goodbye. ~~Chara"~~_

_The words were drowned out._

_Soon after though, if you went back to the same place, you would see a small pile of dust next to the body of a young girl in a green and yellow striped sweater. A single buttercup is wrapped around her wrist._

**Undermortality**

**An Undertale AU**

My eyes shot open.

“FRISK!! Get’ yo butt over here!”

My thirteen-year-old brother shouted from two rooms away.

“Damien! What have I told you about shouting!?”

“You’re shouting too!”

I rubbed my eyes and looked in a mirror. They were pale yellow, and my pupils were shaped like stars, my mom said. I just thought they looked creepy.

Footsteps entered my room and I looked up. My brother, Damien, was leaning against the doorframe. He rubbed his brown hair and smoothed out his plain green shirt.

“c’mon, Frisk, we’re going hiking!!”

I sighed. “I know, Damien. Just let me get ready. Tell Mom I need five more minutes.”

Damien ran out of my room. “FRISK NEEDS FIVE MORE MINUTES!!”

I grinned and ran a brush through my shoulder-length brown hair. I stuck my snack stash in my black backpack and slid a plush green jacket over my blue and purple striped sweater. I looked in the mirror and laughed. My clothes clashed. I liked it. I picked up my phone and checked my contacts. I sighed. None of my classmates have texted me yet. As if they would want to text the weird kid with the blindfold on. I grabbed my backpack and went downstairs.

My mom scrunched up her face when she saw what I was wearing. But, me being genderless, she let it pass. “Come on, guys!” She laughed and ran out the door. “The first person to the car sits in the front seat!”

**Notes for the Chapter:**

> Will Frisk win the race?


	2. Hiking

**Summary for the Chapter:**

> In which Frisk learns about Mt. Ebott

**Notes for the Chapter:**

> More JUICE!!  
> Super short chapter plz forgive me

Mom hummed in the driver’s seat as Damien messed with the air conditioning. I sulked in the back seat. “So, where are we hiking?” I asked.

“Mount Ebott, of course,” she replied.

“Isn’t that the mountain that swallowed a bunch of kids?” Damien asked.

I laughed. “What are you talking about, Damien?”

I caught him smiling mischievously in the side mirror. “Well, you see, Mt. Ebott is rumored to have something to do with the disappearance of several people. Legend has it that anyone who climbs to the top never comes back down.”

Mom laughed. “Those are just silly rumors, Damien.”

Damien shook his head in denial. “It’s not.”

“It is,” I cut in. Damien sighed dramatically. “Why does everyone doubt me?”

“Nobody doubts you, Damien,” Mom said. “I do,” I offered helpfully. “Frisk!” Mom scolded.

I grinned. “oh look, we’re here.” Damien looked outside. “Yes, we are. Let’s go!” Mom parked the car and Damien opened the door. He jumped outside. “Wow, look! That’s so high!” he pointed up. “Are we going to be climbing to the top?”

Mom shrugged. “If you want,” she said.

“Yes!” Damien shot his fist into the air and ran up the mountain trail. “Last one to the top is a rotten egg!”

“Hey!” I opened my door and got out. I slammed the door and ran after him.

“Wait up!” Mom laughed and ran after us.

**Notes for the Chapter:**

> Dang Frisk lost  
> Their gonna be tired Oof


	3. Discovery

**Summary for the Chapter:**

> Frisk discovers something.

“Frisk! Put down your snacks and eat your lunch!” Mom scolded. We were resting in the middle of the trail, where a picnic table had been conveniently placed on a small outcrop with a great view. I smiled innocently and stuffed the bag of chips I was eating back into my backpack. I brushed off the crumbs from my fingers and focused on consuming the spaghetti my mom made. I used the plastic fork to scoop up some of it and put it into my mouth. Wow. It was still warm. The flavor of the sauce mixed with the flavor of the spaghetti and made me drool even when I was chewing it. Damien scrunched up his face at the taste.

“Mom, why’d you have to put _sauce_ on mine?” he whined. Mom laughed.

“Because that’s how you eat spaghetti, Damien,” Mom batted her eyelashes. I finished the last strand of spaghetti and licked my lips.

“If you want, Damien, I can eat yours for you.”

His face instantly brightened up and he nodded eagerly. Mom shook her head and grinned. “Damien, if you use your sibling to get away with not eating your lunch, then I’m pretty sure you’ll be okay with no homemade sugar cookies.”

His smile dropped. He immediately began shoving spaghetti into his mouth and chewing it. Mom and I looked away in disgust. “I’m going to take a walk.” I got up, grabbed my share of the cookies, and backed away. I then proceeded to walk up the trail.

When I was a few feet away from my family, I took a break in the shade of a large pine tree. A small forest grew behind it. I sat down, grabbed a sugar cookie from the small plastic bag, inhaled the sugary smell, and bit into the cookie. The burst of flavor made me sigh and lean further on the tree. I put my snack down on the plastic bag on the grass and went to think. I stared up at the peak of Mt. Ebott. I wondered where my dad was right now. He was in the U.S Navy and had been in Korea for about 6 years now. I wondered if he got that letter we sent to him last year on my 16th birthday. I reached down for my cookie and immediately jerked my hand away.

“Aww man…” I groaned. There were ants on my sugar cookie. I picked up the cookie, brushed the ants away, and placed it on the grass. “I hope the Ant god will accept my sacrifice.”

I then took the bag with the extra cookies and walked behind the tree. A glint of something gold caught my eye. I knelt down and spotted what had caught my attention.

Was that a _locket_?

**Notes for the Chapter:**

> uh huh! The locket! In this AU Frisk finds the locket first before falling down.


End file.
